Air intake systems provide necessary air to internal combustion engines to aid in the combustion process. Conventional intake systems either draw air from inside the engine compartment, or they draw air from outside the vehicle via an exterior intake port. Systems designed where the air is drawn from inside the engine compartment commonly suffer a drawback of drawing in warmer and less dense air than exterior air. This reduces the efficiency of the engine compared with the use of cooler exterior air. A solution to address the shortcoming of these systems is to draw in cooler exterior air. However, systems designed where the air is drawn in via an exterior intake port commonly suffer a drawback of drawing in air that includes water or particles, which can block the engine intake, inhibit airflow, or damage the engine. Solutions have been proposed to address the shortcomings of these exterior intake port systems.
U.S. Pat. No. 5,564,513 to Wible et al. discloses an exterior air intake system for an internal combustion engine that includes an intake port disposed under the vehicle hood in front of the radiator. The intake port includes a filter for removing solid particulates from the intake air and for separating water from the air. The intake port, however, requires a large space forward of the radiator under the hood of the vehicle, which is difficult to fit within the compact engine compartments of contemporary vehicles. Further, due to the filter's proximity to the exterior opening of the port, the filter may have a propensity to clog quickly to inhibit airflow and may require frequent changing.
U.S. Pat. No. 6,510,832 issued to Maurer et al. discloses an exterior air intake system for an internal combustion engine that is aimed at avoiding water intake by providing a main air inlet to exterior air, an auxiliary air inlet, a moisture sensor, and an electric valve to close the main air inlet. When moisture is sensed in the main inlet, the electric valve closes the main inlet and air is drawn from the engine compartment into the auxiliary air inlet. The Maurer system, however, requires pneumatic or electro-pneumatic drives and an electrical moisture sensor. These complicated elements may be subject to an increased chance of failure.
U.S. Pat. No. 5,022,479 to Kiser et al. discloses a rectangular channel formed in the vehicle hood that includes a forward ambient air inlet and a rear air outlet. The channel includes a series of baffles to capture moisture from air flowing therethrough. A sealing sleeve is provided to bridge between the channel and the engine air cleaner. The Kiser system has drawbacks in that it occupies a large amount of hood space and relies upon a special sleeve design to connect with the air cleaner system.
U.S. Pat. No. 4,971,172 to Hoffman et al. discloses air ducts formed in the hood of a truck to eliminate water and heavier particles from the air stream. The intake pathway includes vertical ducts with drainholes to permit the drainage of water collected in the pathway. The intake pathways occupy a large amount of hood space and create a long conduit to the intake system, which inhibits efficient airflow.
Accordingly, a need exists for an improved air intake system. In addition, a need exists for a method of efficiently obtaining cool exterior air for an internal combustion engine having low moisture and/or particulate content.